Crankshaft lapping machine



5 SheetsSheet 1 I 203 I76 37] I99 20'; X- 205 I67 w. H. woon CRANKSHAFT LAPPING MACHINE Filed Feb. 18, 1959 July 11, 1939.

MLLACE H. W001] July 11, 1939. w. H. wooo 2,166,086

CRANKSHAF'T LAPPING MACHINE Filed Feb. 18, 1939 5 Sheets-Sheet 2 24/ 40 243 Z I42 FIG. 2 248 I, 1.

WALLACE H. W001? 94 0002 11 wm.m m-

July 11, 1939. I w H, w 2,166,086

CRANKSHAFT LAPPING MACHINEY Filed Feb. 18, 1959 5 Sheets-Sheet 5 I 7 1440 I64 8 26 i4] I I4 I63 WALLACE H.

July 11, .1939. w. H. WOOD 2,166,086

CRANKSHAFT LAPPING MACHINE Filed Feb. 18, 1939 5 Sheets-Sheet 4 y- 1939- .w. H. WOOD 2,166,086

CRANKSHAFT LAPPING MACHINE Filed Feb. 18, 1939 5 Sheets-Sheet 5 1 3 WALLACE H. W001:

7 6 280 IE. 1 .Z

Patented July 11, 1939 i UNITED STATES CRANKSHAFT LAPPING MACHINE Wallace H. Wood, Worcester, Mass, assignor to Norton Company, Worcester, Mass., at corpora tion of Massachusetts Application February 18,

11 Claims.

The invention relates to abrading machines, and more particularly to a crankshaft lapping machine.

One object of the invention is to provide a simple and thoroughly practical lapping machine for simultaneously lapping or polishing a plurality of crankpins and main bearings on a crankshaft. A further object of the invention is to provide a crankshaft lapping machine in which all of the crankpins and main bearings may be simultaneously lapped. Another object of the invention is to provide a crankshaft lapping machine for simultaneously lapping the crankpins and bearings of the crankshaft, in which a plurality of lapping arms are hydraulically operated. A further object of the invention is to provide a crankshaft lapping machine in which all of the bearing and crank lapping arms are mounted on a movable frame which is movable to and from an operating position by a hydraulically operated mechanism. A further object of the invention is to provide a hydraulically operated clamping mechanism for clamping the lapping arms in an indexed position during the loading operation.

A further object of the invention is to provide a hydraulically operated footstock for aiding in supporting the work. A further object of the invention is to provide a single control valve for interlocking the various hydraulic mechanisms of the machine. Another object of the invention is to provide a plurality of stops or latches to restrict the movement of the control valve so as to interlock the various hydraulically operated mechanisms of the machine, whereby all must be operated in a definite and predetermined cycle. Other objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts, as will be exemplified in the structure to be hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings, in which is shown one of various possible embodiments of the mechanical features of this invention,

Fig. 1 is a front elevation of the improved crankshaft lapping machine;

Fig. 2 is an end elevation, on an enlarged scale, of the improved crankshaft lapping machine;

Fig. 3 is a diagrammatic illustration of the hydraulic actuating mechanism and piping together with the control valve and the interlocking stop or latch mechanism therefor;

Fig. 4 is a cross sectional view, on an enlarged 1939, Serial No. 257,059

scale, taken approximately on the line 4-4 of Fig. 1;

Fig. 5 is a fragmentary sectional View, taken approximately on the line 5-5 of Fig. 2, showing the lapping arm clamping mechanism;

Fig. 6 is a fragmentary end elevation of a crank lapping arm and its supporting and clamping mechanism;

Fig. '7 is a fragmentary cross sectional view, on an enlarged scale, taken approximately on the line l-l of Fig. 5;

Fig. 8 is a fragmentary plan view, partly in section, of the control valve mechanism shown in Fig. 1;

Fig. 9 is a vertical sectional view, on an enlarged scale, taken approximately on the line 99 of Fig. 1;

Fig. 10 is a fragmentary cross sectional view, taken approximately on the line I0I0 of Fig. 8;

Fig. 11 is a fragmentary cross sectional view, taken approximately on the line I ll l of Fig. 8;

Fig. 12 is a vertical sectional view, taken approximately on the line I2|2 of Fig. 9; and

Fig. 13 is a fragmentary front elevation, on an enlarged scale, of the valve controlling mechanism, having the displacement cylinders broken away and shown in section.

A crankshaft lapping machine has been illustrated in the drawings comprising a base 20 which supports a longitudinally reciprocable work supporting table 2|. Table ways are provided between the base 20 and the table 2| which in the preferred form are of an anti-friction type. The base 20 is provided with a plate 26 which is fixed to the base 20 and is provided at its edge portions with grooves 21 and 28 which serve as inner raceways for a pair of spaced rows of anti-friction balls 29 and 30, respectively. A cage is provided between the races to space the balls 29 and 30 longitudinally, as desired. This construction forms an anti-friction way whereby the table 2| together with a headstock 22 and a footstock 23 may be readily reciprocated during the lapping operation.

H eadstock The headstock 22 is provided with a rotatable spindle 33 which is supported in bearings (not shown). The spindle 33 is rotated from any suitable source of power, such as an overhead belt drive or a self-contained electric motor. In the preferred construction, an electric motor 34 is mounted in the base 20 of the machine. The motor 34 is provided with a driving pulley 35 Which is connected by multiple V-belts 36 with a pulley 3'! on the headstock 22. The headstock construction has not been illustrated in. detail in the present application since this headstock is not considered to be a part of the present invention and, furthermore, it is identical with that shown in the prior U. S. Patent No. 2,092,734 dated September 7, 1937, to which reference may be had for details of disclosure not found herein.

A clutch 38 (Figs. 3 and 4) within the headstock 22 serves to connect the pulley 31 to rotate the spindle 33 and also to reciprocate the table 2|. A clutch shifting yoke 39 is pivotally mounted on a rock shaft 40 in the headstock. It is desirable to provide an automatic control for the headstock clutch 38 which in the preferred form comprises a fluid pressure operated cylinder 4| having a piston 42 slidably mounted therein. A piston rod 43 is connected at its lower end to the piston 42 and at its upper end by pin 44 with a yoked end of the arm 45 which is fixedly mounted on the rock shaft 40. When fluid under pressure is admitted through a pipe 46' into a cylinder chamber 41 above the piston 42, it thereby causes a downward movement of the piston 42 and a counterclockwise movement of the arms 45 and 39 to move the clutch member 38 toward the right to engage the power drive to start the rotation of the headstock spindle 33 and the reciprocation of the table 2|. Similarly, when fluid under pressure is admitted through a pipe 48 into a cylinder chamber 49 below the piston 42, thus causing an upward movement of the piston 42 and a rocking of the levers 45 and 39 in a clockwise r direction to shift the clutch member 38 toward the left (Fig. 4), the clutch 38 is disengaged, thus disconnecting the power drive and stopping the rotation of the headstock spindle 33 and thereby stopping the oscillation or reciprocation of the work supporting table 2|.

Table reciprocation In the lapping of crankpins and main bearing of an automotive camshaft, it is desirable to provide arelative reciprocatory movement between -the crankshaft or camshaft being lapped and the lapping or abrading elements to prevent production of abrasive grain markings on the pins and bearings of the crankshafts or the cams and bearings of the camshafts. In the present case, the work table 2| is arranged for a longitudinal reciprocatory movement which is preferably accomplished by transmission of the rotary motion of the headstock spindle 33 into a reciprocatory movement of the table 2|. The specific mechanism for reciprocating the table 2| has-not been illustrated in the present case, since this mechanism is identical with that shown in the prior U. S. Patent No. 2,092,734 dated September '7, 1937, to which reference may be had for details of the table reciprocating mechanism not found herein.

Footstoc'lc One end of the crankshaft 24 is supported by a footstock 23 which is provided with a footstock center which is journalled in bearings 53 and 54 within a hollow slidably mounted sleeve 55. The sleeve 55 is slidably keyed by means of a key 56 within an aperture in the footstock frame.

A fluid pressure actuating mechanism is provided for moving the footstock center 5| rapidly to and from an operative position to support one end of the crankshaft 24 within the machine. This mechanism comprises a fluid pressure cylinder 58 having a slidably mounted piston 59 contained therein. The piston 59 is connected to one end of a piston rod 60 which is connected to a pin 5!. The central portion of the pin 6| is slabbed off on opposite sides so as to slide within an elongated slot 62 formed in an enlarged end portion of the piston rod 60. The pin 6| serves as a central pivotal connection between a pair of toggle levers 63 and 64. The toggle lever 64 is connected to the footstock frame by means of a stud 35. The other end of the toggle lever 63 is connected by a stud 63 with a slidably mounted hollow sleeve 61 which slides within an aperture 68 within the sleeve 55. The sleeve 5'5 is held against rotation by means of a pin 69 which is carried by the sleeve 6? and rides within an elongated slot in the sleeve 55. A spring H] is contained within the sleeve 61 and is interposed between the end of an aperture of the sleeve 61 and a thrust collar H.

When fluid under pressure is admitted through a pipe '52 to a cylinder chamber 13, the piston 59 is moved downwardly and the toggle levers 63 and 64 are moved from dotted line positions 63a and 6411 into the full line positions 63 and 64 (Fig. 3) which serves to move the sleeve 6'! into the position illustrated. This movement serves to compress the spring l3 and, through the connecting parts, moves the sleeve 55 and the footstock center 5| into operative supporting engagement with the end of the crankshaft 24. During this movement, fluid is exhausted from a cylinderchamber I4 through a pipe l5. The admission to and exhaust of fluid from the footstock operating cylinder 58 will be hereinafter described. The footstock is identical with that shown in the prior United States Patent No. 2,117,960 dated May 17, 1938, to which reference may be had for details of disclosure not contained herein.

Lapping arm support It is desirable to provide a movable support for a plurality of lapping arms so that they may simultaneously and quickly be moved into an operative or inoperative position as desired. A pair of spaced arms 83, only one of which has been illustrated in the drawings (Fig. 2), are mounted on a rock shaft 8i which is supported in bearings on the rear of the machine base 20. The arms 8i! are provided with horizontally extending portions which are connected by two spaced bars 82 and 83 which serve as slide bars or ways for supporting a plurality of lapping arms to be hereinafter described. The lapping arm assembly supported by the arms 80 is arranged so that it may be automatically moved to and from an operating position to facilitate loading of crankshafts into the machine and removing them therefrom after a lapping operation has been completed. In order to move the entire lapping arm assembly to and from an operative position, a fluid pressure mechanism is provided including a fluid pressure cylinder 84 which is pivotally mounted by means of a stud 85 within the base 20 of the machine. A piston 86 is slidably mounted within the cylinder 84 and is connected to one end of a piston rod 81. The other end of the piston rod 81 is connected by means of a stud 88 with an arm 89 pivotally mounted on a shaft 9!] supported within the base 20. The other end of the arm 89 is connected by a stud 9| to one end of a link 92. 75'

The other end of the link 92 is connected'by means of a stud 93 with a toggle lever 94. The adjacent ends of the toggle lever 94 and a toggle lever 95 are connected by means of a stud 96. The toggle lever 94 is connected at its other end by means of a stud 91 with the base 20. The toggle lever 95 is connected by a stud 98 with an arm 99 which is fixedly mounted on the rock shaft M and is arranged to rock the shaft 8| together with the arms and all of the crankpin and bearing lapping arms together with their supporting and actuating mechanisms either into or away from an operating position.

The levers 89, 92, 94 and 95, as shown in full line positions (Fig. 2), are in a position to hold the arm 99 together with the entire lapping arm assembly in operating position. After the lapping operation has been completed, fluid under pressure is admitted to the cylinder 84 to cause the piston 86 and piston rod 81 to move toward the right (Fig. 2) to shift the levers 89, 92, 94 and and also the arm 99 into the dotted line positions, 89a, 92a, 94a and 95a and 99a. This movement serves to rock the arms 80 in a clockwise direction (Fig. 2) to move the entire lapping arm assembly to an inoperative position.

Fluid pressure system A fluid pressure system is provided to control the admission of fluid under preesure to the cylinder 84. A pump I00 in the base 20 of the machine draws fluid through a pipe IOI from a reservoir I02 within the base 20 of the machine and passes fluid under pressure through a pipe I03 to a manually operable control valve I04. The valve I04 is of a piston type having a valve stem I05 which is provided at its outer end with a spool-shaped member I06 and is connected by means of a stud or pin I01 mounted on one end of a control lever I08. The control lever I08 is pivotally mounted on the front of the machine base by means of a stud I09 which is supported on the base 20 of the machine. A plurality of valve pistons H0, III, H2, H3 and H4 are formed integral with the valve stem I05. Fluid under pressure passing through the pipe I03 passes into a valve chamber II5 located between the valve pistons I I2 and H3 and passes out through a pipe I I6 into a cycle control valve Ill. The manually operated control valve I04 serves also as a stop and start valve for the cycle control valve I I1. At the same time, fluid under pressure is admitted through the pipe H6, and fluid under pressure also passes through a pipe I I8 into'the right-hand end chamber of the cycle control valve I I1. The cycle control valve H1 is a piston type valve comprising a valve stem II9 which has formed integrally therewith valve pistons I20, I2I, I22 and I23. When fluid under pressure is admitted through the pipe I I8 into a chamber I24 between the valve piston I23 and the end cap of the valve II1, the valve stem H9 is moved in a manner to be hereinafter described into its extreme left-hand position (Fig. 3).

Fluid under pressure passing through the pipe I03 into the valve chamber I I5 passes out through the pipe H6 into a valve chamber I25 located between the valve pistons I2I and I22 and passes out through a pipe I26 into a cylinder chamber I21 to move the piston 86 into the position illustrated in Figs. 2 and 3 so that the lapping arm assembly is in an operative position.

During the admission of fluid under pressure to the cylinder chamber I21, fluid is exhausted from a cylinder chamber I28 at the other end of the cylinder 84' through a pipe I 29, through a valve chamber I30 located between the valve pistons I22 and I23, and passes out through a pipe I3I into a hydraulic control mechanism to be hereinafter described. A fluid pressure relief valve I32 is connected in the pipe line I03 and serves to by-pass excess fluid under pressure within the pipe I03 to the reservoir I02.

The cycle control valve I I1 also serves to control the admission of fluid under pressure to the rootstock actuating cylinder 58. The pipe 12 is connected to the pipe I26 and serves to convey fluid under pressure to the footstock cylinder chamber 13 simultaneously with the passage of fluid under pressure to the cylinder chamber I21 of the cylinder 84. The pipe 15, which is connected to the cylinder chamber 14 of the cylinder 56, is connected with the pipe I29 so that in the position of the cycle control valve II1 (Fig. 3). fluid will exhaust simultaneously from the cylinder chamber 14 in the cylinder 58 and from the cylinder chamber I28 in the cylinder 84.

When the cycle control valve I04 is shifted into the position illustrated in Fig. 3, fluid under pressure simultaneously enters both the cylinders 58 and the cylinder 84 and, due to the fact that less power is required to move the footstock center than the lapping arm assembly, the footstock center 5I moves first into an operative position in engagement with the end of the work piece 24, after which the lapping arm assembly moves into an operative position adjacent to the crank-- pins and bearings to be lapped.

Lapping arms In order that all of the crank pins and main bearings on the crankshaft 24 may be simultaneously lapped, a plurality of crankpin and bearing lapping arms are provided which correspond in number with the crankpins and bearings to be lapped. As illustrated, there are three main bearing lapping arms I40, MI and I42 There are four crank lapping arms I43, I44, I45 and I46. The main bearing and crankpin lapping arms are supported in spaced relationship with each other so as to simultaneously engage and lap the three main bearings and the four crankpins on the crankshaft 24.

The bearing lapping arms and crankpin lapping arms are substantially identical in construction. The bearing lapping arms are stationary while lapping the main bearings which are concentric with the axis of rotation of the crankshaft 24, whereas the crankpin lapping arms are rocked during the lapping operation due to the fact that they engage a crankpin which revolves about the axis of rotation of the crankshaft 24.

A side elevation of the lapping arm I42 is shown in Figs. 2 and 6. The lapping arm I42 as well as all of the other lapping arms are each provided with a pair of pivotally mounted lap supporting arms I50 and I5I which are provided at their operative ends with partial cylindrical lap supporting blocks I52 and I53, respectively. The arms I50 and I5I are pivotally supported by the studs I54 and I55 on the lapping arm I42. The other ends of the arms I50 and I5I are interconnected by means of a pair of toggle levers I56 and I51 which are connected together at their inner ends by means of a stud I58. The stud I58 slides in an elongated slot I59 in the side plate of the lapping arm I42. When the toggle levers I56 and I51 are in a straight line position (Figs. 2 and 6), the lap supporting members I52 and I53 are maintained in operative engagement to hold an abrasive or lapping element in operative contact with a portion of the crankshaft 24. The lap supporting arms I58 and I5I are arranged to be automatically moved into and away from an operative position, and in the preferred construction a hydraulically operated mechanism is provided for actuating the same comprising a fluid pressure cylinder I42a which is either fixedly mounted on or formed integral with the upper end of the lapping arm I 42. A piston M22) is slidably mounted therein and is connected to one end of a piston rod I420. The other end of the piston rod I 42b is connected by a stud E68 with a link 561. The other end of the link I6I is connected to the stud I58 which pivotally connects the adjacent ends of the toggle levers I56 and I51.

It will be readily apparent from the foregoing disclosure that when the piston I421) is moved downwardly, that is, toward the left (Fig. 2), the piston rod I420 and the connecting link I6I will be moved also in a downward direction toward the left which serves to unlock the toggle levers I56 and I51 and thereby to rock the lap supporting arms I58 and 15I together with the lap supporting elements I52 and I53 to an inoperative position out of engagement with the crankshaft 28. When fluid under pressure is passed through a flexible pipe I421 into a cylinder chamber I42e, the piston I i-2h will be moved downwardly to move the toggle levers I56 and I51 into a straight-line position (Figs. 2 and 6) to move the abrasive lapping element into an operative position in engagement with the work piece 28 for a lapping operation. Similarly, when fluid under pressure is admitted to a flexible pipe I42) to cause an upward movement of the piston I821) toward the right (Figs. 2 and 6) the toggle levers I56 and I51 will be unlocked to move the lapping elements to an inoperative position.

It is to be noted in the drawings (Fig. 3) that each of the lapping arms is provided with an independent fluid operated piston and cylinder as well as piston rods which have been designated in the diagram with the same reference numerals as the lapping arm on which it is mounted, the cylinders being designated by the letter a, the pistons by the letter I), the piston rods by the letter 0, and the cylinder chambers by the letter c.

It is desirable that all of the lapping elements represented by the supporting members I52 and I53 (Fig, 2) be moved into and away from an operative position simultaneously. This is preferably accomplished by providing a pair of longitudinally extending pipes or manifolds I63 and E64 which are fixedly supported on the spaced arms 88 and serve as a common source of fluid under pressure which may be forced either through the flexible pipe M211 to move the lapping elements into an operative position, or when the fluid under pressure is reversed, to flow through the flexible pipe 142) simultaneously to move all of the lapping elements to an inoperative position after the lapping operation has been completed. The admission to and exhaust of fluid from the manifold or pipes 163 and I64 is controlled by the cycle control valve H1. A pipe I65 is connected between the manifold or pipe I63 and the valve chamber I25 and serves in the position of the valve II1 (Fig. 3) to admit fluid under pressure to the manifold or pipe I63, into the cylinder chamber I 42c, and simultaneously to all of the other corresponding cylinder chambers in the cylinders on each of the lapping arms to move and hold said lap supporting arms in an operative position for a lapping operation. A pipe I66 connected between the manifold or pipe I64 and the valve chamber I38 so that in the position of the valve II1 (Fig. 3), fluid may be exhausted from the upper cylinder chambers on each of the lapping arms, through the manifold I64 and the valve chamber 138, into the pipe I3I into a fluid control system to be hereinafter described.

Each of the lapping arms I48 to I48 inclusive is pivotally supported. The details of the support for the lapping arms being identical, only one support has been illustrated in detail. An arm I15 is pivotally mounted on a supporting member I16 which is clamped in adjusted position on the guide rods 82 and 83. The lower end of the arm I15 is pivotally mounted to the supporting member I16 by means of a pivotal connection I11. A pivotal connection I18 serves to connect the arm I15 with the lapping arm I42 so that the arm I42 is free to move. All of the lapping arms, both crankpin and main bearings, are mounted in the same manner so that when the lapping elements are clamped in engagement with a crankpin and main bearing, the crank lapping arms may follow as the crankpin is revolved to produce the desired lapping action.

A flexible abrasive paper or cloth is preferably utilized as an abrading or lapping medium, Each of the lapping arms is provided with a separate strip of continuous abrasive paper which wraps around the crankpin or main bearing and is held in position thereagainst by the lap supporting members I52 and I53. A rod 188 is supported on the rear of each of the supporting members I16 by means of a bracket I 81 and serves as a support for a reel I82 of flexible abrasive paper I83. The abrasive paper I83 passes through guides I84 and I85 supported on the under side of the supporting member I16 and passes through a series of rollers I86 carried by a bracket I81. The abrasive paper above described wraps around a main bearing or a crankpin of the crankshaft 24 and is supported by the lap supporting members I52 and I53. The worn or used abrasive paper is wound up on a reel I88 which is supported by a stud I88 carried by a bracket I88 supported on the lap supporting arm I58.

Th lap supporting members I52 and E53 are mounted so that they may float or move relative to the arms I58 and I5I, so that the lap supporting members I52 and I53 are self-aligning when brought into operative engagement to support the abrasive paper on a crankpin on the main bearing for a lapping operation.

The brackets I81 and I98 are fixedly mounted to the floating lap supporting members I52 and I53. A holding pawl I8I cooperating with a ratchet wheel on the end of the reel I88 serves to prevent unreeling of the worn abrasive paper I83 wound up on the reel I88 when the lap supporting arms I58 and I5I are moved to and from an operating position. As illustrated in the drawings, the abrasive paper is fed manually when desired by the operator by manually turning the reel I88. Only one of the reels I88 and the associated parts to guide the abrasive lapping paper I83 through the reel I88 has been illustrated in detail. Each lapping arm is provided with similar equipment supported on a separate supporting member I16. The abrasive paper and wind-up reels for each of the lapping arms are illustrated in the front elevation of the machine (Fig. 1).

The lapping arm I48 is supplied with a strip of abrasive paper I which is wound up on a reel I86, The lapping arm I43is provided with a strip plates 2I0 and 2.

of abrasive paper I91 and the used portion thereof is wound up on a reel I98. The lapping arm I44 is supplied with a strip of abrasive paper I99, the used portion of which is wound up on a reel 200. The lapping arm MI is supplied with a strip of abrasive paper 20!, the used portion of which is wound up on a reel 202. The lapping arm I45 is provided with a strip of abrasive paper 203, the used portion of which is wound up on a reel 204. The lapping arm I46 is supplied with a strip of abrasive paper 205, the used portion of which is wound up on a reel 206. Inasmuch as the abrasive paper supporting reels and guide means are identical for each of the lapping arms, only one of these mechanisms has been completely illustrated, as shown in Fig. 2.

It is desirable to provide a guiding means for guiding the lapping arms during their swinging movement as they follow the revolving crankpins, and to provide a clamping mechanism to clamp all of the lapping arms in their indexed position relative to the supports I16 before the lap supporting members I52 and I53 are released from operative position and the lapping arm assembly is swung to an inoperative position to facilitate loading of the machine. It is desirable to provide such a clamping device so that when the arms 80 are moved to an inoperative position after a new crankshaft has been loaded into the machine, all of the lapping arms will be in proper indexed position so that the lap supporting members I52 and I53 may be automatically brought into engagement simultaneously with each of the crank pins and main bearings of the crankshaft 24.

In order that the lapping elements may be guided in their swinging movement and held against lateral movement during reciprocation or oscillation of the crankshaft 24 during the lapping operation, a pair of parallel guiding plates 2I0 and 2H are fixedly mounted on the supporting bracket I16 and are spaced apart by a distance equal to the thickness of the lapping arm I42. The lapping arm I42 is guided thereby and is held against lateral movement by the guide The lapping arm I40 is similarly guided by guide plates 2I2 and 2I3. The lapping arm I43 is guided by guiding plates 2I4 and 2I5. The lapping arm I44 is guided by the guiding plates 2I6 and 2I1. The lapping arm MI is guided by guide plates 2I8 and 2H3. The lapping arm I45 is guided by guide plates 220 and 22!, and the lapping arm I46 is guided by the guiding plates 222 and 223.

Lap a1'mclamping device In order to provide means for simultaneously clamping all of the crankpins and the bearing lapping arms in their respective indexed positions, the guide plates 2I0, 2I2, 2I4, 2I6, 2I8, 220 and 222 are each provided with a groove or guideway 224 which supports a slidably mounted member 225 having cam surface depressions 226 formed in the slidably mounted member 225. It will be readily apparent that if the slide 225 is moved upwardly (Figs. 5 and '1) relative to the guiding plate 2I0, the cam depression 226 engaging the fixed cams 221 and 228 will cause the slide member 225 to move toward the right (Fig. 6) and thereby bind or clamp the lapping arm I42 in a fixed position relative to the guiding plates 2 I and 2I I. Each of the lapping arms I40 to I46 inclusive is provided with an identical clamping means, consequently only one of these clamps has been illustrated in detail. The guide plates 2I2, 2I4, 2I6, 2I8, 220 and 222 are each provided with a clamping slide 2I2a, 2I4a, 2I0a, 2I8a, 220a and 222a, respectively.

In order to simultaneously clamp all of the lapping arms, a mechanism is provided for simultaneously actuating the clamping slides 225, 2I2a, 2I4a, 2I6a 2I8a, 220a and 2220.. As illustrated in the drawings, a shaft 23I is rotatably supported in apertures in the guiding plates 2I0 to 223 inclusive. Each of the clamping slides is provided with an elongated slot 232 (Fig. 7). The shaft 23I carries an eccentric 233 which rides within the elongated slot 232. When the shaft 23I is rotated, the eccentric 233 rotating within the elongated slot 232 causes the clamping slide 225 to move relative to the guiding plates 2| 0 and 2I I, so as to clamp the lapping arm I42 in an indexed position relative to the plate. The shaft 23I is provided with a plurality of eccentric members corresponding to the eccentric 233, each of which is arranged to engage elongated slots in the respective clamping slides 2I2a, 2| 4a, 2I6a, 2I8a, 220a and 222a.

Clamp actuating motor A vane type fluid pressure motor 240 is providede for rocking the shaft 23I simultaneously to clamp and release all of the lapping arms. The motor 240 is provided with a rotor shaft 24I which supports a rotary vane 242. The rotor shaft 24I projects from the motor casing toward the left (Fig. 5). An arm 243 is supported on one end of the rotor shaft 24I. The arm 243 is provided with an enlarged head 244 having a notch 245 formed in the outer end thereof. A lever 246 is fixedly mounted on the shaft 23I and is provided with a spring-pressed plunger 241 which is arranged to engage the notch 245 to lock the lever 246 to the lever 243 so that the rotation of the vane 242 of the motor 240 will be transmitted to rotate the shaft 23I to clamp or release all of the lapping arms. The plunger 241 is connected with a knob 248 by means of which the plunger 241 may be withdrawn from the notch 245 so that the clamping mechanism may be operated manually if desired.

Interlocks In order to attain one object of the invention, it is desirable to provide suitable interlocks so that various mechanisms of the machine will operate in a predetermined sequence. When a crankshaft has been loaded into the machine, the control lever I08 is moved to shift the valve I04 to start the cycle of operation. The movement of the valve I04 serves to shift the cycle control valve II1 by an intermittent stepped movement controlled by a mechanism to be hereinafter described, so that the moving parts of the machine operate in the following sequence:

(a) Footstock center 5| moves in to grip work.

(b) Arms 80 which support the crankpin bearing lapping arms swing forward into an operating position.

(c) Jaws close onto work.

((2) Lapping arms are unclamped.

(e) Headstock starts rotating.

(1) Headstock stops rotation.

(91) Lapping arms are clamped in an index position.

(h) Jaws open.

(2') Arms 80 swing back to an inoperative position.

(7') Footstock. center moves out of engagement with the work to release the same, after which the crankshaft may be unloaded from the machine.

The cycle controlvalvel I1 is shifted from one end position to anothcrby fluid under pressure conveyed to endchamb'ersat oppositeends of said valve. In order to obtain the desired operating cycle, the ports fromthe valve II! to the various hydraulically operated units, namely footstock cylinder 58, lap arm engaging cylinders, clamp rotary motor 240, and headstock clutch cylinder 4 I, are arranged so that fluid under pressure is admitted to the various units in the desired sequence so as to obtain a predetermined cycle of operation. It is desirable to control the shifting of the valve stem 9 of the valve II'I so that it moves intermittently to allow each individual mechanism suflicient time to operate before the valve shifts to admit fluid to the next mechanism. In order to control the movement of the valve II'I, astop plate 259 is supported by brackets 25I and 252 which are connected to opposite ends of the valve stem 9. The stop plate 259 is-provided with a stop abutment 253 which engages a stepped plate 254 when the valve stem H9 moves toward the right at the end of a lapping cycle. The stepped plate 254 is provided with stepped stops 255, 25B, 251 and 258 which are engaged'by the stop abutment 253 of the plate 259 successively to limit the "movement of the valve stem I'IQ toward the right. The stepped plate 254 is supported by a guide 259 which serves to take the thrustof the valve stem H9.

The stepped plate 254 is moved vertically in timed relation with'the operation of the various mechanisms of the machine successively-to present successive stops 'into operative relation with the stop abutment 253 which moves with the valve stem I I9. The'vertical movement of the plate 25 is preferably controlled by'a fluid operated cylinder 259 having a piston 26I slidably g mounted therein. The piston'ZBI is connected to the lower end of a pistonrod 252, the upper end of which is connected to the stepped stop plate 254.

A similar stop abutment-265 is provide-d on the plate 25a. The stop abutment-265 is arranged in the path of a vertically movable stepped stop plate 256 having a plurality of steppedstop abutments 261,298, 2ii9and 210. A'guide 2"II 'is provided for the vertically movable stepped plate 255. This guide block is supported in fixed relation with the base of the machine and serves to take up the thrust of the moving valve stem I'I9 when the valve is being moved toward'the left atthe start of a lapping cycle. The stepped'stop plate 256 is similarly'movedvertically in amanner to be hereinafter described bymeans of a fluid pressure mechanism comprising a cylinder 275 having a piston 2T5 slidably'mounted therein. A piston rod 21'? is connected at its lower end to the piston 2Y6 and'at'itsupper end is connected to move thestepped stop pl'ate'266 to produce an intermittent "stepped movement of the cycle control valve II'I as the valve moves toward the left at the'start of a'lappingcycle.

The cylinders 269 "and 215 are connected to receive the exhaust of fluid from each "side of the system. The shape of the stepped'stop plates 254'and 266 is determined bythe fluid volume contained in the various fluid pressure operated mechanisms of the machine sothat'when fluid exhausts from one mechanism, the volume will be sufficient to raise the pistons 26l or 276, as the case may be, a sufii'cient distance to bring the next stop on the stepped stop plate into operative position'with the stop plate 250. Fluid under pressure exhausting from the foodstock out through a pipeor passage 28I into a cylinder chamber 282 below the piston 21% intermittently to raise the piston, thus moving the stepped stop plate 266 vertically to bring successive steps into operative relation with the stop abutment 265 of the plate 250.

Similarly, when the cycle control valve III is -moved into its-reverse position,fluid is exhausted from the various hydraulically controlled units into a valvechamber 285 located between the valve pistons I29 and I 2| in the'cycle control valve III, through a pipe 286, into a valve chamber 28? located between the valve pistons III] and III of the manually operated valve IEl. Fluid passes from the valve chamber 28l through a pipe or passage 288, into a cylinder chamber 289 to raise'the piston 26I a distance governed by the volumetric exhaust of fluidfrom the operating mechanism.

The stepped stop plates 254 and 266 serves to limit the'movement of the valve stem H9 either toward the right or-toward the left, respectively, so that the various hydraulically operated mechanisms will operate in a definite sequence. In order to slow down the movement of the'valve piston H9 before the stop abutments 255, 251

and 258, respectively, are engaged by the stop abutment 253, a throttle valve 299 is placed in the exhaust pipe line 29I so that'when the valve stem H9 is moved toward the left, fluid which is exhausted from the left-hand end chamber of the valve II I through the pipe 395 passes out through a valve chamber 292 located between the valve pistons 'I II and H2 and out through the pipe =29I, throttle valve 295 and pipe 299 into the'reservoir I132. The valve 299 is normally held inan upward position by means of a-spring and may be partially closed automatically by means of the adjustable'screws 294 "2'95 and 296 carried by the plate 259 engaging the head of the valve 299 and throttling the fluid to slow down the movement of the valve stem H9.

'Similarly,when the valve "stem H9 of the valve H1 is moved toward the right by fluid under pressure after a lapping operation has been completed, fluid exhausts from the end chamber I24, through a pipe H8, into a valve chamber IE5 lo- 'cated between the valve pistons I 52 and H3, and passes out through a pipe 291, a throttle valve 298,-and a pipe 299 into the reservoir I92. The throttle valve 298 is similarly closed automatically by means of a plurality of adjustable screws 399, 30I and 392 which are carried by the plate 250 and which serve to slow down the movement of the valve stem H9 as the abutment 265 on the plate 259 is moved into the various steps. on the stepped stop plate 266. The operation of this improved machine will be readily apparent from the foregoing disclosure. The positions of the parts show the machine in an operating position and the lapping elements in operative engagement with the crankshaft being lapped. The lapping operation proceeds to'the desired extent. After a predetermined lapping operation has been completed, the control lever I99 is rocked in a counterclockwise direction. This movement serves to shift the valve stem I05 toward the right, thus changing the direction of flow of fluid. Fluid under pressure passing through the pipe I03 enters a valve chamber 292 located between the valve pistons II I and H2 and passes out through a pipe 305 into the left-hand end chamber in the cycle control valve II! to start the valve stem I I9 moving toward the right.

In the position of the valve shown in Fig. 3, the stop abutment 2B5 bears against the stop surface 261 of the stepped stop plate 266. When fluid under pressure is admitted through the pipe 305 into the left-hand end chamber of the valve II I, the valve stem H9 moves toward the right into the position illustrated in Figs. 12 and 13 with the stop abutment 253 of. the plate 250 engaging the step 255 on the stepped plate 254. This movement of the valve H'I shifts the valve piston I2I so that fluid within the headstock clutch cylinder chamber 41 may exhaust through the pipe 46 into the valve chamber 285 and through the valve chamber 281 and out through the pipe or passage 288 into the cylinder chamber 289. The volume of fluid within the cylinder chamber 41 raises the piston 26I slightly from the bottom of the cylinder 260 into the position illustrated in Fig. 13, in which position the fluid within the left-hand end chamber of the valve I I! may continue the movement of the valve stem H9 toward the right. At the same time fluid is exhausted through the pipe 45, the valve piston I22 has moved toward the right sufliciently to admit fluid under pressure through the pipe 48 to raise the piston 42 and disengage the headstock clutch 38, thereby stopping the rotation of the headstock 22 and the reciprocation of the work supporting table 2|.

The pressure within the left-hand end chamber of the valve H'I then shifts the valve stem H9 a further distance toward the right until the stop abutment 253 of the plate 250 engages the step 256 of the plate 254 which temporarily prevents further shifting of the valve stem H9. During this shifting movement of the valve stem H9, the adjustable screw 302 engages and actuates the throttle valve 298 to retard the exhaust of fluid from the end chamber I24 of the valve III to slow down the shifting movement of the valve stem H9.

When the valve stem H9 slows down as it approaches a second predetermined position, fluid within the clamping motor may exhaust through the pipe 243 and through the valve chamber 285, the valve chamber 281, and passage 288, into the cylinder chamber 289 below the piston 26L thus raising the piston 23I and stepped stop plate 254. During this exhausting movement, the valve piston I22 has moved sufficiently toward the right to uncover the port at the end of the pipe 244 so as to admit fluid under pressure through the pipe 244 into the clamping motor 240 to rotate the vane 242 in a clockwise direction to clamp all the lapping arms in an indexed position.

The exhaust fluid from the clamping motor 240 is suflicient to raise the plate 254 so that the valve stem H9 may continue its movement toward the right until the stop abutment 253 of the plate 250 and the valve stem H9 slows down as it approaches the step 25'! of the stepped plate 254. During this movement the adjustable screw 30I engages and actuates the throttle valve 298 to slow down the movement of the valve stem H9 and prevent the stop abutment 253 from engaging the stepped plate 254 at a rapid rate. This movement of the valve stem H9 shifts the valve piston I2I a suflicient distance toward the right to uncover a port at the end of the pipe I which allows fluid within all of the lapping arm lap shoe actuating cylinders to exhaust from below the pistons. This exhaust fluid passes through the valve chamber 285, the valve chamber 287, through the pipe or passage 288 into the cylinder chamber 289 to raise the piston 26!. The fluid volume within the lapping arm lap actuating cylinders is suflicient to raise the piston 23I and the stepped plate 254 a sufficient distance so that the valve stem H9 continues its movement a further distance toward the right. During this exhaust of fluid from the lap arm lap actuating cylinders, the piston I 22 has moved a suflicient distance toward the right to uncover the port at the end of the pipe I65 so as to admit fluid under pressure through the pipe I56 simultaneously to release all of the lapelements from engagement with the crankpins and main bearings of the crankshaft 24.

The stepped plate 254 having been raised a sufficient distance, allows the valve stem H9 to move to its extreme right-hand position with the abutment 253 in engagement with the step 258 on the stepped plate 254. During movement into this position, the screw 300 engages the throttle valve 298 and slows down the movement of the valve stem H9. This latter movement of the valve stem H9 into its extreme right-hand position serves to move the valve piston I2I toward the right a sufficient distance to uncover the port at the end of the pipe I23, thereby allowing fluid simultaneously to exhaust from the chamber 13 of the footstock actuating cylinder 58 and from the cylinder chamber I21 of the lap arm assembly actuating cylinder 94. At the same time, the valve piston I22 has moved a suiiicient distance toward the right to uncover the port at the end of the pipe I29 so that fluid under pressure within the chamber I25 is admitted through the pipe I29 simultaneously into a cylinder chamber I4 below the piston 59 of the footstock actuating cylinder 58 and into the chamber I28 at the left-hand end of the lap arm assembly actuating cylinder 84 which serves to withdraw the footstock center 5! and then to move the lapping arm assembly to its inoperative position to facilitate unloading the lapped crankshaft and to allow a new shaft to be placed in the machine.

During this stopping of the lapping cycle, the valve piston H4 of the valve I04 has moved toward the right so that fluid within the cylinder chamber 282 of the cylinder 275 may exhaust through the pipe 28I into the valve chamber 280 and out through the pipe 299 into the reservoir I02 so that when the parts are positioned at the end of the lapping cycle, the piston 226 will be in its extreme downward position ready for the next lapping cycle.

The crankshaft 24 which has been lapped is then removed from the machine and a new shaft to be lapped is placed in position on the work supporting cradles 3H] and 3! I and rolled into an operating position in vertical alignment with the work centers. The control lever I08 is then rocked in a clockwise direction to shift the valve I04 toward the left to initiate a lapping cycle. At the start of the lapping cycle, the stop abutment 253 is in engagement with the step 258 of the stepped plate 254. When the valve stem I05 is moved to its left-hand end position, fluid under pressure is admitted through pipe I I8 toend chamber I24 to start the valve stem I I9 moving toward the position illustrated in Fig. 3. The

valve stem H9 moves toward the left and its movement is slowed down as the abutment 255 approaches the step 2'50 on the stepped plate 266. This movement serves to admit fluid under pressure to operate the footstock piston 59 and to admit fluid under pressure to the lap arm assembly cylinder 84 to move the lapping arm assembly into operative position. During this movement fluid is exhausted from the opposite ends of the lap arm assembly cylinder 84 and the footstock cylinder 58 through the pipe I29 and into the cylinder chamber 282 to raise the stepped plate 266 so that the valve stem H9 may continue its movement toward the left until the stop abutment 265 approaches the step 269 of the stepped plate 266, which movement uncovers a port to admit fluid through the pipe I 65 which moves all of the lap arm pistons upwardly to clamp the lapping elements in operative position on the pins and main bearings of the crankshaft 24. During this movement fluid within the other side of the lap arm cylinders passes. out through the pipe IBS and into the cylinder chamber 282 again to raise the piston 2155 and the stepped plate 266 so that the valve stem l [5 may move so that the abutment 265 approaches the step 268. This further movement of the valve stem I I9 serves to admit fluid under pressure through the pipe 243 to unclamp the lapping arms. During the unclamping movement fluid exhausts from the other side of the clamping motor 249 through the pipe 244 and into the cylinder chamber 282 to again raise the stepped plate 266. The plate 265 rises a sufficient distance so that the valve stem H9 may continue its movement toward the left until the abutment 265 approaches the step 261 of the plate 2.5!! which uncovers a port to admit fluid under pressure through the pipe 46 into the chamber il of the headstock clutch cylinder 4| toengage the clutch 38 and start the work rotation and work support reciprocation, after which the lapping operation proceeds for the desired time interval. This cycle of operation is then repeated.

During the shifting of the valve stem M9 toward the left, the screws 294, 295 and 296 successively actuate the throttle valve 290 to throttle the exhaust of fluid from the left-hand cylinder chamber of the cycle control valve I I; to slow down the movement of the valve stem H9 dur ing the various steps thereof.

It will thus be seen that there has been, provided by this invention apparatus in which the various. objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments may be made of the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. In a hydraulically operated crankshaft lapping machine having a plurality of fluid motors independently to operate the footstock, the lap arm assembly frame, the opposed lapping elements, the clamping mechanism and the headstock clutch, a cycle control valve, end chambers in said cycle control valve whereby the valve may be shifted in either direction by fluid under pressure, a manually operable valve to admit fluid under pressure to either end chamber of said control valve, a throttle valve to control the exhaust of fluid from said end chambers, and

means including a plurality of spaced adjustable members whereby the throttle valve may be actuated intermittently to slow down the control valve movement sufficiently so that one mechanism may complete its operation before the next mechanism starts whereby the footstock, lap arm assembly, lap elements, lap arm clamping mechanism and headstock clutch operate in the desired and predetermined sequence.

2. In a hydraulically operated crankshaft lapping machine having a plurality of fluid motors independently to operate the footstock, the lap arm assembly frame, the opposed lapping elements, the clamping mechanism and the headstock clutch, a cycle control valve, end chambers in said cycle control valve whereby the valve may be shifted in either direction by fluid under pressure, a manually operable valve to admit fluid under pressure to either end chamber of said control Valve at the start or finish of a lapping operation, an independent throttle valve associated with each of said end chambers to control the exhaust of fluid therefrom and thereby to control the speed of movement of the cycle control valve, and means including a plurality of spaced adjustable members whereby the throttle valves may be actuated in timed relation with the cycle control valve movement to slow down the movement of the control valve sufliciently so that one mechanism may complete its operation before the next movement starts so that the footstock, lap arm assembly, lapping elements, lapping arm. clamping mechanism and headstock clutch may be operated in the desired and predetermined sequence.

3. In a hydraulically operated crankshaft lapping machine having independent fluid motors to operate each mechanism, a cycle control mechanism including a control valve, said control valve being arranged successively to admit fluid under pressure to said motors independently to actuate the several mechanisms in a predetermined sequence, a manually operable valve to admit fluid under pressure to either end of said control valve at the start or finish of a lapping operation, a safety device including a stepped plate so as to prevent a continuous rapid shift-- ing of said control valve, and a displacement piston and cylinder operatively connected to actuate said plate, said displacement piston being actuated intermittently by exhaust of fluid from said motors.

4. In a hydraulically operated crankshaft lapping machine having a plurality of fluid motors independently to actuate a footstock, a lap arm assembly frame, opposed lapping elements, a lap arm clamping mechanism and a headstock clutch, a cycle control valve, said control valve having end chambers whereby the valve is actuated by fluid under pressure, a manually operable valve to admit fluid under pressure to either end of said control valve at the start or finish of a lapping operation, a stepped plate which is arranged to prevent a continuous movement of the control valve, an independent throttle valve associated with each of said end chambers to control the exhaust of fluid therefrom, a displacement piston and cylinder operatively connected to move said plate, said displacement cylinder being displaced successively by exhaust of fluid from said motors, said displacement piston and cylinder and stepped plate serving as a safety device to prevent shifting of the cycle control valve unless said motors have functioned, and means actuated in timed relation with the movement of said cycle control valve intermittently to actuate said throttle valves to slow down the shifting movement of the cycle valve to allow a sufiicient time interval for each successive mechanism to function.

5. In a lapping machine having a plurality of lapping arms, a movable frame to support said arms, a clamping mechanism for clamping said arms relative to said frame, a rotatable work support including a motor driven headstock and footstock, means including a clutch to start said headstock, a plurality of fluid motors respectively connected to actuate said footstock, said frame, said lapping arms, said clamping mechanism and said headstock clutch, a control valve to control the admission to and exhaust of fluid from all of said motors, end chambers in said control valve, a manually operable start and stop valve to admit fluid under pressure to either one or the other of said end chambers, and means including an intermittently actuated stepped stop plate to produce an intermittent stepped movement of the control valve so as to interlock the several mechanisms of the machine.

6. In a lapping machine as claimed in claim 1, the combination with the parts and features therein specified, of a stepped plate which serves as a safety device during the stepped movement of said control valve when moved in either direction, a displacement cylinder and piston operatively connected independently to actuate each of said stepped plates, said displacement cylinder being arranged successively to receive exhaust fluid from said motors whereby the stepped plate is intermittently raised, the exhaust fluid from each of said motors being suflicient to displace said piston to raise the stepped plate a predetermined extent to allow the control valve to move to its next position.

'7. In a crankshaft lapping machine as claimed in claim 1, the combination with the parts and features therein specified, of a safety device for controlling the intermittent movement of the control valve comprising a stepped plate, a displacement piston and cylinder actuated during the shifting of the control valve at the start of the lapping cycle by fluid exhausting successively from said motors to control the intermittent shifting of the control valve so as to provide an interlocking of the mechanism.

8. In a crankshaft lapping machine as claimed in claim 1, the combination with the parts and features therein specified, of a stepped plate, a displacement piston and cylinder to actuate said plate at the start of the lapping cycle by fluid exhausting successively from said motors, a second stepped plate, and displacement piston and cylinder to actuate said second plate during the shifting of the control valve at the end of a lapping cycle by fiuid exhausting successively from the opposed sides of said motors to control the intermittent shifting of the control valve so as to interlock the actuation of the mechanisms during the stopping of the machine at the end of the lapping cycle.

9. In a lapping machine as claimed in claim 1, the combination with the parts and features therein specified, of a displacement piston and cylinder, connections between said piston and said stepped plate, and fluid connections between all of said motors, said control valve and displacement cylinder whereby the exhaust fluid from said motors serves to actuate said stepped plate.

10. In a lapping machine as claimed in claim 1, the combination with the parts and features therein specified, of a safety device including a stepped plate, a displacement piston and cylinder, connections between said piston and stepped plate, and fiuid connections between all of said motors, said control valve and displacement cylinder, whereby exhaust fluid from said motors serves to displace said piston and thereby actuate the stepped plate, said steps on the plate being arranged so that exhaust fluid from one or more of said motors serves to raise the plate sufliciently to facilitate a further continued movement of the control valve.

11. In a lapping machine having a plurality of lapping arms, a movable frame to support said arms, a clampingmechanism for clamping said arms relative to said frame, a rotatable work support including a motor driven headstock and a footstock, means including a clutch to start said headstock, a plurality of fluid motors respectively connected to actuate said footstock, said frame, said lapping arms, said clamping mechanism and said headstock clutch, a control valve to control the admission to and exhaust of fluid from all of said motors, end chambers in said control valve, a manually operable start and stop valve to admit fluid under pressure to either one or the other of said end chambers, an independent throttle valve operatively connected independently to control the exhaust of fluid from each of said end chambers so as to control the speed of movement of the control valve in either direction, and a plurality of spaced adjustable screws which are movable with said valve to actuate said throttle valves periodically to slow down the shifting movement of the control valve so as to allow sufficient time for successive fluid motors to actuate their respective mechanisms before the control valve admits fluid under pressure to successive motors.

WALLACE H. WOOD. 

